Stratigraphy and lithology
Article # 30_2023 submitted on 03/20/2023 displayed on website on 08/18/2023
13 p.
pdf Microfacies and sedimentary environment of Ilam and Laffan Formations in Bangestan Mountain, Southwest of Iran
*The article is presented in English.

Ilam (Cenomanian-Santonian) and Laffan (Coniacian) Formations are part of the Bangestan Group, which are located between Gurpi Formation on the top and Sarvak Formation on the bottom. The Ilam Formation is considered one of the main hydrocarbon reservoirs of the Bangestan Group in the Southwest of Iran. In this study, Ilam and Laffan Formations have been investigated in two sections of Tang-e Ban and Tang-e Abolfares areas. The purpose of this study is to identify and determine the microfacies and sedimentary environment of Ilam and Laffan Formations. The petrographic studies and facies analysis in the Tang-e Ban and Tang-e Abolfares sections led to the identification of 9 microfacies types that were deposited in lagoon, shoal, and open sea environments, which were located in the inner, middle, and outer-ramp setting. Due to the type of microfacies studied in both sections, the absence of large barrier reef, slump structures, calciturbidite, oncoids and pisoids, could consider that this sequence has been deposited in a homoclinal carbonate ramp environment.

Keywords: Ilam Formation, Laffan Formation, Bangestan Group, microfacies type, sedimentary environment, carbonate ramp, Southwest of Iran.
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